Technical Field
The present invention relates to a unitary razor blade and a shaving razor cartridge using the same, and more particularly, to a razor blade which is shaped into a geometrical structure so as to achieve the maximized strength thereof.
Background Art
Shaving should give a sense of cleanness and avoid any cut or injury. Factors which affect the shaving performance include a frictional resistance between a razor blade edge and skin and the sharpness of the razor blade edge. Such factors include the force of a cutter applied to hair by the razor blade.
Increase in the number of razor blades in a shaving razor improves shaving efficiency of the shaving razor and well distributes a pressure to the skin, but also increases a drag force. Also, the increased number of razor blades takes more space or narrows the gap between cutting edges. Such increased area taken by the razor blades may adversely affect the shaving performance, and the narrower gap of the razor blades may deteriorate the shaving performance, and make it difficult to remove the shaving remainder. Conversely, if the gap between the razor blades is wider, the shaving performance may improve but users are more likely to be injured or cut by the razor blades. Accordingly, it is very important to properly adjust the gap between the razor blades.
To narrow the gap between the razor blades with the shaving performance secured and to remove the shaving remainder without difficulty, the thickness of the razor blades should be inevitably thin. However, if the razor blades are too thin, they cannot cut hair but may be easily deformed and deteriorate durability. Accordingly, it is required to provide a thin and strong razor blade.
As shown in FIGS. 1 and 2, a general wet shaving razor includes a grip 2, a cartridge 3 and a plurality of razor blades 4.
The cartridge 3 includes a housing 33 which accommodates therein the plurality of razor blades 4, a guard rubber 31 and a lubricant band 32. The cartridge 3 includes a connection portion 22 which is connected to the grip 2 so that the housing 33 rotates with respect to a rational shaft.
FIG. 3 is a sectional view of the cartridge 3, taken along line A-A′ in FIG. 2. As shown therein, the razor blades 4 has a cutting edge 41 mounted on a supporter 43 to maintain a certain level of strength. Generally, the supporter 43 includes a strong aluminum alloy. That is, the cutting edge 41 is mounted on the supporter 43 by welding to prevent the razor blades 4 from being deformed or damaged when used.
The cutting edge 41 is located adjacently to a shaving direction 11 to reduce the risk of cut and ensure a comfortable shaving. An edge portion of the razor blades 4 is inclined at an acute angle to a shaving plan 10 to provide a comfortable shaving and prevents the cutting edge 41 to be worn to some extent.
However, the conventional technology requires a welding process to combine the cutting edge 41 and the supporter 43 which are manufactured in separate processes, incurring a lot of expenses and deteriorating manufacturing efficiency due to additional processes.